The present application is directed generally to wrenches and, more specifically, to adjustable open-ended wrenches.
Wrenches are used for a variety of purposes including tightening and loosening workpieces such as pipes, bolts and nuts. Many wrenches include a head having a pair of opposing jaws that are spaced apart to form an opening. A handle may extend from the head for positioning the opening on the workpieces and exerting a force on the workpiece. Use of the open-ended wrench usually includes approaching the workpiece from the side and positioning the opening around the workpiece. Once the opening is positioned, force is applied to the handle to rotate the workpiece.
One type of wrench includes adjustable jaws for adjusting the size of the opening to accommodate different workpieces. One or both of the jaws are laterally adjustable to control a size of the opening. An adjustment mechanism, such as a cylindrical member, is positioned in the head and operatively connected to one or both of the jaws. Rotation of the cylindrical member in a first direction causes the jaws to move laterally outward and increase the size of the opening. Rotation in a second direction causes the jaws to move laterally inward and reduce the opening size.
While adjustable wrenches are desirable for their ability to fit multiple workpieces, there are many disadvantages. A first disadvantage is the wrenches may be larger than fixed-sized wrenches. The adjustable wrench usually includes a large head sized to accommodate the jaws at a distance to fit the largest workpiece. Further, adjustable wrenches may be expensive due to increase complexity of the movable jaws and rotating cylinder.